From b2d1cea7595975f69d4e440d89e9beca531cf1bf Mon Sep 17 00:00:00 2001
From: Ovear <ovearj@gmail.com>
Date: Fri, 17 Feb 2023 16:31:00 +0800
Subject: [PATCH] fix: RoundRobin strategy of load balance when called multiple
 times (#390)

---
 adapter/outboundgroup/loadbalance.go | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/adapter/outboundgroup/loadbalance.go b/adapter/outboundgroup/loadbalance.go
index 7dc4d3d3c..48bd49942 100644
--- a/adapter/outboundgroup/loadbalance.go
+++ b/adapter/outboundgroup/loadbalance.go
@@ -115,11 +115,20 @@ func (lb *LoadBalance) SupportUDP() bool {
 }
 
 func strategyRoundRobin() strategyFn {
+	flag := true
 	idx := 0
 	return func(proxies []C.Proxy, metadata *C.Metadata) C.Proxy {
 		length := len(proxies)
 		for i := 0; i < length; i++ {
-			idx = (idx + 1) % length
+			flag = !flag
+			if flag {
+				idx = (idx - 1) % length
+			} else {
+				idx = (idx + 2) % length
+			}
+			if idx < 0 {
+				idx = idx + length
+			}
 			proxy := proxies[idx]
 			if proxy.Alive() {
 				return proxy